EEA anvil snap ring activator

Abstract

A surgical fastening apparatus and associated method of use is disclosed. The surgical fastening apparatus includes a handle assembly, a central body portion extending from the handle assembly, and a distal head portion including an anvil head assembly. The anvil head assembly includes an anvil head defining an interior recess, an activator plate, a deformable member, and a securing member. The anvil center rod assembly defines a longitudinal axis and is pivotably connected to the anvil head assembly about a pivot axis. The anvil center rod assembly includes a configured to contact the anvil head assembly upon an actuation of the surgical fastening apparatus. Upon the actuation of the surgical fastening apparatus, the deformable member is configured to deform such that the activator plate is advanced distally into the interior recess to facilitate the anvil head pivoting about the pivot axis.

The invention claimed is: 
     
       1. A surgical fastening apparatus, comprising:
 a handle assembly; 
 a central body portion extending from the handle assembly; and 
 a distal head portion including a shell assembly and an anvil assembly, the anvil assembly including:
 an anvil head assembly including an anvil head defining an interior recess supporting an activator plate, a deformable member positioned distally of the activator plate, and a securing member positioned proximally of the activator plate, the anvil head having a post extending proximally therefrom; and 
 an anvil center rod assembly defining a longitudinal axis, the anvil head being pivotably connected to the anvil center rod assembly about a pivot axis, the anvil center rod assembly including a plunger in mechanical communication with the anvil head, the plunger configured to contact the anvil head assembly upon actuation of the handle assembly to cause pivoting of the anvil head about the pivot axis; 
 
 wherein, upon actuation of the handle assembly, the deformable member is configured to deform such that the activator plate is advanced distally into the interior recess to a distal position disengaged from the anvil head to permit the anvil head to pivot about the pivot axis in response to movement of the plunger while the securing member is moved distally to securely engage the post extending from the anvil head to maintain the activator plate in the distal position. 
 
     
     
       2. The surgical fastening apparatus of  claim 1 , wherein the post defines an annular groove configured to securely receive the securing member. 
     
     
       3. The surgical fastening apparatus of  claim 1 , wherein the post defines an aperture therethrough, the aperture configured to align with a throughbore of the anvil center rod assembly. 
     
     
       4. The surgical fastening apparatus of  claim 3 , wherein the aperture and the throughbore are configured to receive a pivot member therethrough to pivotably attach the anvil head assembly with the anvil center rod assembly. 
     
     
       5. The surgical fastening apparatus of  claim 1 , wherein the deformable member includes a body and an extension extending therefrom. 
     
     
       6. The surgical fastening apparatus of  claim 5 , wherein the extension is configured to deform with respect to the body. 
     
     
       7. The surgical fastening apparatus of  claim 1 , wherein the pivot axis is transverse to the longitudinal axis. 
     
     
       8. The surgical fastening apparatus of  claim 1 , wherein the plunger is configured to engage the anvil head assembly at a location offset from the longitudinal axis. 
     
     
       9. The surgical fastening apparatus of  claim 1 , wherein the anvil head assembly includes a cut ring disposed in the interior recess. 
     
     
       10. The surgical fastening apparatus of  claim 9 , wherein the cut ring is configured to receive an annular knife upon the actuation of the handle assembly. 
     
     
       11. The surgical fastening apparatus of  claim 1 , wherein the anvil center rod assembly defines a ridge configured to inhibit the anvil head from pivoting about the pivot axis. 
     
     
       12. The surgical fastening apparatus of  claim 11 , wherein the ridge is configured to engage a lug extending from the activator plate. 
     
     
       13. The surgical fastening apparatus of  claim 11 , wherein, upon actuation of the handle assembly, the lug is configured to move away from the ridge to permit pivoting of the anvil head about the pivot axis. 
     
     
       14. The surgical fastening apparatus of  claim 1 , wherein the anvil center rod assembly includes a sleeve slidably disposed thereon. 
     
     
       15. The surgical fastening apparatus of  claim 14 , wherein the sleeve is configured to engage tissue. 
     
     
       16. The surgical fastening apparatus of  claim 15 , wherein the sleeve is configured to slide proximally upon pivoting of the anvil head about the pivot axis. 
     
     
       17. The surgical fastening apparatus of  claim 1 , wherein the securing member includes a discontinuity defined by a pair of tapered ends. 
     
     
       18. A method of using a surgical fastening apparatus, comprising:
 providing an anvil center rod assembly and an anvil head assembly pivotably attached thereto; 
 actuating the surgical fastening apparatus such that an annular knife contacts a cut ring within the anvil head assembly; 
 advancing the annular knife distally such that the cut ring moves an activation plate and a deformable member distally of the cut ring to cause release of the activation plate from the anvil head assembly, the deformable member having a body and an extension configured to deform relative to the body; and 
 securing the activation plate with a securing ring to maintain the activation plate released relative to the anvil head assembly such that the anvil head assembly is free to pivot relative to the anvil center rod assembly. 
 
     
     
       19. The method of  claim 18 , further including pivoting the anvil head assembly relative to the anvil center rod assembly such that a smaller cross-sectional profile of the surgical fastening apparatus is created.